A concerted study of the cancer cell and its interaction with the host in a coordinated and cooperative effort by four major groups of investigators is being carried out at the Roswell Park Memorial Institute. The groups are cooperating in studies on (a) the nature and functions of cell membranes and cell periphery as related to cell growth and host response, (b) the chromosomal composition of the cancer cell as related to the control of cancer cell constituents and cancer cell products, and (c) the ability of the host to respond immunologically to the cancer cell. Studies will be made of the same cells and cell lines so that their efforts will be coordinated from a common base line. This is in contrast to the situation which so frequently exists that different cells are studied by different groups so that final direct correlations are impossible. Indeed this coordination and cooperation will include sharing of facilities and equipment such as animal, washing, cell culture, electron microscope, and radiation facilities.